Dipper front



June 18, 1929. o. w. ANDERSEN 1,717,907

DIPPER FRONT Filed 001;. 27, 1927 |l@ O o 0 o V'o b 1 Pk I Patented June 18, 1929.

UNITED STATES PATENT OFFICE.

OSCAR VJ. ANDERSEN, 0F OAK PAR-K, ILLINOIS, ASSIGNOR TO PETTIBONE MULLIKEN COMPANY, A CORPORATION OF NEW YORK.

DIPPER FRONT.

Application filed October 27, 1927. Serial No. 229,249.

My invention relates to front, cast metal portions of clippers or buckets for use in excavating, dredging, or similar work.

One of my objects is to reduce the weight and cost of construction of such fronts particularly when formed of manganese steel, without sacrificing strength of the structure, thereby permitting the buckets to be made of lighter weight with the advantage of reduction in cost of construction and operation and increase in eliiciency in the use of the bucket.

Another object. is to provide a construction of dipper front by which the molding thereof may be facilitated, improved castings produced and danger of fracture of the metal in cooling, minimized.

Referring to the accompanying drawings:

Figure 1 is a view in side elevation of a dipper front constructed in accordance with my invention. Figure 2 is a plan sectional view of the front taken at the line 2 on Fig. 1 and viewed in the direction of the arrow; and Figure 8, a view in vertical sectional. elevation of the front, the section being taken at the line 3 on Fig. 2 and viewed in the direction of the arrow.

1 have illustrated my invention as embodied in a dipper front of a common and wellknown form for assembly with the rear wall and side wall forming portion of the bucket, though without any intention of limiting my invention to such form of front.

he front shown which is of general curved shape in plan is provided at opposite sides, adjacent its upper edge, with rearwardly extending plate-like portions 4- containing openings 5 (the opening in one only of the plate portions 4 being shown) for receiving the bail pivots, the side portions of the front being represented as containing series of rivet-receiving holes 6 at which the front would be connected with the rear wall and side wall forming portion of the bucket.

The particular illustrated construction of front is formed to provide along its upper edge a lip portion '1' which is customarily equipped with dipper teeth (not shown) secured thereto in any desired manner. The main portion of the dipper front below the lip is of corrugated form with the corrugations extending lengthwise of the front as shown, the lower edge portion of the dipper front. and along which the corrugations referred to extend to the extreme bottom of the front, being thickened as represented at 8. The corrugated portion of the front, at any given plan cross section thereof is of uniform tlnckness and of the same thickness at any given plan cross section except at the lower thickened part 8 of the front which, while of uniform thickness at any given plan cross section therethrough, is of greater thickness than the corrugated portion above it.

The forming of the dipper front with the corrugated portion as described is of advantage not only because the corrugations afford great stifiness to the structure permitting the front to be formed much thinner than in the case of a plain front andconsequently lightening the weight of the structure with the manifest advantage, but also because the casting of such a front, as compared with the casting of fronts of ribbed form of a non-uniform cross sectional thickness, is facilitated and danger of fracturing the metal in cooling, which is very apt to occur in such ribbed constructions, is minimized.

In this connection it will be noted that the connection between the relatively thin corrugated portion and the relatively thick adjacent portion of the front is along an undulating line whereby the corrugated portion buckles in the subsequent cooling of the relatively thick portion, in casting, thereby greatly reducing the stresses created in the metal at the juncture of these portions compared with the stresses produced in structures which present straight-line junctures or the equivalents thereof between the relatively thin and the relatively thick portions thereof, the greatest reduction of stresses be-- ing effected where the metal of the corrugated portion is of substantially uniform thickness and the corrugations are continuous and of curved form as shown.

While I have illustrated and described a particular embodiment of my invention, I do not wish to be understood as intending to limit it thereto as the same may be variously modified and altered without departing from the spirit of my invention.

VJ hat I claim as new, and desire to secure by Letters Patent, is:

1. A cast-metal clipper-front comprising a relatively thick edge portion extending cross wise of the dipper front, and a corrugated portion cast integrally with said edge portion and extending from the latter and crosswise of the dipper front, the corrugations tion and extending from the latter and crosswise of the dipper front, the metal of said corrugated portion at any given plan cross section thereof being of substantially uniform thickness, said corrugations being of such form thatthey will buckle during the contraction of said relatively thick edge portion relative to said corrugated portion in cooling whereby stress at the juncture of said edge portion and said corrugated portion due to the differential cooling of said edge portion and said corrugated portion will be miniinized.

3. A cast-metal dipper-front comprising a relatively thick edge portionextending crosswise of the dipper front, and a corrugated portion cast integrally with said edge portion and extending from the latter and crosswise of the dipper front, said corrugated p'or tion being substantially continuously corrugated throughout its extent the corrugations of said corrugated portions extending lengthwise of the dipper front whereby said corrugated portion will buckle during the contraction of said relatively thick edge portion rel- .ative to said corrugated portion in cooling and stress at the juncture of said edge portion and said corrugated portion due to the differential cooling of said edge portion and said corrugated portion will thereby be min- 7 imizedi tively thick edge portion relative to said corrugated portion in cooling and stress the juncture of said edge portion and said corrugated portion due to the d fferential cooling bf said edge portion and said corrugated portion will thereby be minimized.

5. A cast-metal dipper-front compris ng a relatively thick edge portion extending crosswise of the dipper-front, and a corrugated portion cast integrally with said edge portion and extending from the latter and crosswise of the dipper front, said corrugated portion being substantially continuously corrugated throughout its extent with the metal of said corrugated portion at any given plan cross section thereof being of substantially uniform thickness whereby said corrugated portion will buckle during the contraction of said relatively thick edge portion relative to said corrugated portion in cooling and stress at the juncture of said edge portion and said corrugated portion due to the differential cooling of said edge portion and said corrugated portion will thereby be minimized.

6. A cast-metal dipper-front comprising a relatively thick edge portion extending crosswise of the dipper front, and a corrugated portion cast integrally with said edge portion and extending from the latter and crosswise of the dipper front, the metal of said corrugated portion at any given plan cross section thereof being of substantially uniform thickness and said corrugations be-' ing substantially continuously curved throughout the extent of said corrugated portion and extending lengthwise of the dipper front whereby said corrugated portion will buckle during the contraction of said relatively thick edge portion relative to said corrugated portion in cooling and stress at the juncture of said edge portion and said corrugated portion due to the differential cooling of said edge portion and said corrugated portion will thereby be minimized.

7. A cast-metal dipper-front comprising relatively thick opposite edge portions extending crosswise of the dipper front, and a corrugated portion cast integrally with said edge portions and extending from the latter and crosswise of the dipper front, the corrugations of said corrugated portion extending lengthwise of the dipper front and of such form that they will buckle, during the contraction of said relatively thick edge portions relative to said corrugated portion in cooling, whereby stress at the junctures of said edge portions and said corrugated portion due to the differential cooling of said edge portions and said corrugated portion will be minimized.

8. A cast-metal dipper-front comprising relatively thick opposite edge portions extending crosswise of the dipper front, and a corrugated portion cast integrally with said edge portions and extending from the latter and crosswise of the dipper front, the metal of said corrugated portion at any given plan cross section thereof being of substantially uniform thickness and the corrugations of said corrugated portion extending lengthwise of the dipper front and of such form that they will buckle, during the contraction of said relatively thick edge portions relative to said corrugated portion in cooling, Whereby stress at the junctures of said edge portions and said corrugated portion due to the diiferential cooling of said edge portions and said corrugated portion will be minimized.

9. A cast-metal dipper-front comprising relatively thick opposite edge portions ex tending crosswise of the dipper front, and a corrugated portion cast integrally with said edge portions and extending from the latter and crosswise of the dipper front, said corrugated portion being substantially continuously corrugated throughout its extent, the corrugations of said corrugated portion eX- teuding lengthwise of the dipper front Whereby said corrugated portion will buckle du ing the contraction of said relatively thick edge portions relative to said corrugated portion in cooling and stress at the juncture of said edge portions and said corrugated portion due to the difierential cooling of said edge portions and said corrugated portion will thereby be minimized.

10. A cast-metal dipper-front comprising relatively thick opposite edge portions eX- tending crosswise of the dipper front, and a corrugated portion cast integrally With said edge portions and extending from the latter and crosswise of the dipper front, the corrugations of said corrugated portion being substantially continuously curved throughout the extent of said corrugated portion and extending lengthwise of the dipper front Whereby said corrugated portion Will buckle during the contraction of said relatively thick edge portions relative to said corrugated portion in cooling and stress at the juncture of said edge portions and said corrugated portion due to the differential cooling of said edge portions and said corrugated portion will thereby be minimized.

OSCAR W. ANDERSEN. 

